Fluid and Electrolyte Balance Flashcards
Infant total body fluid
70-80%
More prone to dehydration due to 50% being ECF
3 y/o total body fluid
65%
15 y/o total body fluid
60%
Maintenance fluid calculation
4ml/kg/hr for first 10kg
2ml/kg/hr for second 10kg
1ml/kg/hr for remainder
Respiratory acidosis
Caused by diminished or inadequate pulmonary ventilation –> elevated pCO2 levels, decreased plasma pH
Causes of depressed respiratory system
Head injury, narcotic drugs, cystic fibrosis, OPD, pneumonia, atelectasis, factors that affect chest wall
Metabolic acidosis
Caused by gain of nonvolatile acids or the loss of base –> decreased plasma bicarbonate (HCO3-) and plasma pH
Causes of metabolic acidosis (acid gain or base loss)
Acid gain - indigestion, starvation, infection, aspirin ingestion (acetylsalicylic acid)
Bicarb loss - diarrhea
Respiratory alkalosis
Caused by an increase in rate and depth of pulmonary ventilation –> decreased pCO2 levels, elevated plasma pH
Causes of increased pulmonary ventilation (rate and depth)
Emotions, mechanical ventilation
Metabolic alkalosis
Caused by gain of base or loss of acid –> elevated plasma HCO3- and plasma pH
Causes of acid loss
Vomiting, diuretic therapy
Isotonic dehydration
Fluid loss involving extracellular fluid and circulating blood volume
Sodium may decrease, chloride decrease, potassium stable
Hypotonic dehydration
Water shifts from extracellular fluid to intracellular fluid in an attempt to establish osmotic equilibrium
Sodium and chloride decrease, potassium varies
Hypertonic dehydration
Water shifts from intracellular fluid to extracellular fluid
Sodium and chloride increase, potassium varies
Can lead to neurologic disturbances
Mild dehydration
Loss of 5% of pre-illness weight
Alert, pale, dry, decreased UOP, decreased skin turgor, VS normal
Moderate dehydration
loss of 6-9% of pre-illness weight
Irritable, grey, poor skin turgor, very dry, oliguria, increased HR
Severe dehydration
Loss of 10% of pre-illness weight
Lethargic, mottled, very poor skin turgor, parched, marked oliguria, increased HR, rapid/thready pulse, low BP, delayed cap refill
Best sign of hydration status
Daily weight
Urine specific gravity in dehydration
> 1.030 (high), concentrated
Initial replacement for dehydration
Isotonic solution at rate of 10-20 ml/kg
Contraindicated in hypertonic dehydration due to water toxicity
Sodium bicarbonate may be added to correct acidosis
Potassium not added until kidney function is ensured (child voiding)
Causes of acute gastroenteritis
Rotavirus - most common cause
Bacterial - E. coli, salmonella, shigella, C. diff
Oral rehydration therapy
Start early when child starts having diarrhea
90 mEq/L of sodium - Pedialyte
Systemic damage caused by burns (4)
Respiratory compromise due to inhalation injury
Hypovolemic shock
Accelerated metabolic rate - increased body temp, increased nutritional needs
Local infection, sepsis
Inhalation injury can cause swelling for ____
2-5 days
Hypovolemic shock can occur when total body surface area covers ____
15-20% of body
Hypovolemic shock signs
Hypotension, increased HR, weak/thready pulse, prolonged cap refill, cool extremities
First sign of sepsis
Disorientation
Electrolyte imbalances caused by burns
Elevated fasting blood glucose
Hyponatremia
Hyperkalemia due to cell lysis
Metabolic acidosis due to hypovolemia and cell damage
